XmlSchemaUnique 类

定义

按 WWW 联合会 (W3C) 指定的方式显示 unique 来自 XML 架构的元素。 此类可用于标识一组元素中的唯一约束。

public ref class XmlSchemaUnique : System::Xml::Schema::XmlSchemaIdentityConstraint
public class XmlSchemaUnique : System.Xml.Schema.XmlSchemaIdentityConstraint
type XmlSchemaUnique = class
    inherit XmlSchemaIdentityConstraint
Public Class XmlSchemaUnique
Inherits XmlSchemaIdentityConstraint
继承

示例

下例显示了 XmlSchemaUnique 类的用法。

#using <System.Xml.dll>

using namespace System;
using namespace System::Xml;
using namespace System::Xml::Schema;

ref class XMLSchemaExamples
{
private:
    static void ValidationCallbackOne(Object^ sender, ValidationEventArgs^ args)
    {
        Console::WriteLine(args->Message);
    }

public:
    static void Main()
    {
        XmlSchema^ schema = gcnew XmlSchema();

        // <xs:complexType name="customerOrderType">
        XmlSchemaComplexType^ customerOrderType = gcnew XmlSchemaComplexType();
        customerOrderType->Name = "customerOrderType";

        // <xs:sequence>
        XmlSchemaSequence^ sequence1 = gcnew XmlSchemaSequence();

        // <xs:element name="item" minOccurs="0" maxOccurs="unbounded">
        XmlSchemaElement^ item = gcnew XmlSchemaElement();
        item->MinOccurs = 0;
        item->MaxOccursString = "unbounded";
        item->Name = "item";

        // <xs:complexType>
        XmlSchemaComplexType^ ct1 = gcnew XmlSchemaComplexType();

        // <xs:attribute name="itemID" type="xs:string"/>
        XmlSchemaAttribute^ itemID = gcnew XmlSchemaAttribute();
        itemID->Name = "itemID";
        itemID->SchemaTypeName = gcnew XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

        // </xs:complexType>
        ct1->Attributes->Add(itemID);

        // </xs:element>
        item->SchemaType = ct1;

        // </xs:sequence>
        sequence1->Items->Add(item);
        customerOrderType->Particle = sequence1;

        // <xs:attribute name="CustomerID" type="xs:string"/>
        XmlSchemaAttribute^ CustomerID = gcnew XmlSchemaAttribute();
        CustomerID->Name = "CustomerID";
        CustomerID->SchemaTypeName = gcnew XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

        customerOrderType->Attributes->Add(CustomerID);

        // </xs:complexType>
        schema->Items->Add(customerOrderType);

        // <xs:element name="ordersByCustomer">
        XmlSchemaElement^ ordersByCustomer = gcnew XmlSchemaElement();
        ordersByCustomer->Name = "ordersByCustomer";

        // <xs:complexType>
        XmlSchemaComplexType^ ct2 = gcnew XmlSchemaComplexType();

        // <xs:sequence>
        XmlSchemaSequence^ sequence2 = gcnew XmlSchemaSequence();

        // <xs:element name="customerOrders" type="customerOrderType" minOccurs="0" maxOccurs="unbounded" />
        XmlSchemaElement^ customerOrders = gcnew XmlSchemaElement();
        customerOrders->MinOccurs = 0;
        customerOrders->MaxOccursString = "unbounded";
        customerOrders->Name = "customerOrders";
        customerOrders->SchemaTypeName = gcnew XmlQualifiedName("customerOrderType", "");

        // </xs:sequence>
        sequence2->Items->Add(customerOrders);

        // </xs:complexType>
        ct2->Particle = sequence2;
        ordersByCustomer->SchemaType = ct2;

        // <xs:unique name="oneCustomerOrdersforEachCustomerID">
        XmlSchemaUnique^ element_unique = gcnew XmlSchemaUnique();
        element_unique->Name = "oneCustomerOrdersforEachCustomerID";

        // <xs:selector xpath="customerOrders"/>
        element_unique->Selector = gcnew XmlSchemaXPath();
        element_unique->Selector->XPath = "customerOrders";

        // <xs:field xpath="@customerID"/>
        XmlSchemaXPath^ field = gcnew XmlSchemaXPath();
        field->XPath = "@customerID";

        // </xs:unique>
        element_unique->Fields->Add(field);
        ordersByCustomer->Constraints->Add(element_unique);

        // </xs:element>
        schema->Items->Add(ordersByCustomer);

        XmlSchemaSet^ schemaSet = gcnew XmlSchemaSet();
        schemaSet->ValidationEventHandler += gcnew ValidationEventHandler(ValidationCallbackOne);
        schemaSet->Add(schema);
        schemaSet->Compile();

        XmlSchema^ compiledSchema = nullptr;

        for each (XmlSchema^ schema1 in schemaSet->Schemas())
        {
            compiledSchema = schema1;
        }

        XmlNamespaceManager^ nsmgr = gcnew XmlNamespaceManager(gcnew NameTable());
        nsmgr->AddNamespace("xs", "http://www.w3.org/2001/XMLSchema");
        compiledSchema->Write(Console::Out, nsmgr);
    }
};

int main()
{
    XMLSchemaExamples::Main();
    return 0;
}
using System;
using System.Xml;
using System.Xml.Schema;

class XMLSchemaExamples
{
    public static void Main()
    {

        XmlSchema schema = new XmlSchema();

        // <xs:complexType name="customerOrderType">
        XmlSchemaComplexType customerOrderType = new XmlSchemaComplexType();
        customerOrderType.Name = "customerOrderType";

        // <xs:sequence>
        XmlSchemaSequence sequence1 = new XmlSchemaSequence();

        // <xs:element name="item" minOccurs="0" maxOccurs="unbounded">
        XmlSchemaElement item = new XmlSchemaElement();
        item.MinOccurs = 0;
        item.MaxOccursString = "unbounded";
        item.Name = "item";

        // <xs:complexType>
        XmlSchemaComplexType ct1 = new XmlSchemaComplexType();

        // <xs:attribute name="itemID" type="xs:string"/>
        XmlSchemaAttribute itemID = new XmlSchemaAttribute();
        itemID.Name = "itemID";
        itemID.SchemaTypeName = new XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

        // </xs:complexType>
        ct1.Attributes.Add(itemID);

        // </xs:element>
        item.SchemaType = ct1;

        // </xs:sequence>
        sequence1.Items.Add(item);
        customerOrderType.Particle = sequence1;

        // <xs:attribute name="CustomerID" type="xs:string"/>
        XmlSchemaAttribute CustomerID = new XmlSchemaAttribute();
        CustomerID.Name = "CustomerID";
        CustomerID.SchemaTypeName = new XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

        customerOrderType.Attributes.Add(CustomerID);

        // </xs:complexType>
        schema.Items.Add(customerOrderType);

        // <xs:element name="ordersByCustomer">
        XmlSchemaElement ordersByCustomer = new XmlSchemaElement();
        ordersByCustomer.Name = "ordersByCustomer";

        // <xs:complexType>
        XmlSchemaComplexType ct2 = new XmlSchemaComplexType();

        // <xs:sequence>
        XmlSchemaSequence sequence2 = new XmlSchemaSequence();

        // <xs:element name="customerOrders" type="customerOrderType" minOccurs="0" maxOccurs="unbounded" />
        XmlSchemaElement customerOrders = new XmlSchemaElement();
        customerOrders.MinOccurs = 0;
        customerOrders.MaxOccursString = "unbounded";
        customerOrders.Name = "customerOrders";
        customerOrders.SchemaTypeName = new XmlQualifiedName("customerOrderType", "");

        // </xs:sequence>
        sequence2.Items.Add(customerOrders);

        // </xs:complexType>
        ct2.Particle = sequence2;
        ordersByCustomer.SchemaType = ct2;

        // <xs:unique name="oneCustomerOrdersforEachCustomerID">
        XmlSchemaUnique element_unique = new XmlSchemaUnique();
        element_unique.Name = "oneCustomerOrdersforEachCustomerID";

        // <xs:selector xpath="customerOrders"/>
        element_unique.Selector = new XmlSchemaXPath();
        element_unique.Selector.XPath = "customerOrders";

        // <xs:field xpath="@customerID"/>
        XmlSchemaXPath field = new XmlSchemaXPath();
        field.XPath = "@customerID";

        // </xs:unique>
        element_unique.Fields.Add(field);
        ordersByCustomer.Constraints.Add(element_unique);

        // </xs:element>
        schema.Items.Add(ordersByCustomer);

        XmlSchemaSet schemaSet = new XmlSchemaSet();
        schemaSet.ValidationEventHandler += new ValidationEventHandler(ValidationCallbackOne);
        schemaSet.Add(schema);
        schemaSet.Compile();

        XmlSchema compiledSchema = null;

        foreach (XmlSchema schema1 in schemaSet.Schemas())
        {
            compiledSchema = schema1;
        }

        XmlNamespaceManager nsmgr = new XmlNamespaceManager(new NameTable());
        nsmgr.AddNamespace("xs", "http://www.w3.org/2001/XMLSchema");
        compiledSchema.Write(Console.Out, nsmgr);
    }

    public static void ValidationCallbackOne(object sender, ValidationEventArgs args)
    {
        Console.WriteLine(args.Message);
    }
}
Imports System.Xml
Imports System.Xml.Schema

Class XMLSchemaExamples
    Public Shared Sub Main()

        Dim schema As New XmlSchema()

        ' <xs:complexType name="customerOrderType">
        Dim customerOrderType As New XmlSchemaComplexType()
        customerOrderType.Name = "customerOrderType"

        ' <xs:sequence>
        Dim sequence1 As New XmlSchemaSequence()

        ' <xs:element name="item" minOccurs="0" maxOccurs="unbounded">
        Dim item As New XmlSchemaElement()
        item.MinOccurs = 0
        item.MaxOccursString = "unbounded"
        item.Name = "item"

        ' <xs:complexType>
        Dim ct1 As New XmlSchemaComplexType()

        ' <xs:attribute name="itemID" type="xs:string"/>
        Dim itemID As New XmlSchemaAttribute()
        itemID.Name = "itemID"
        itemID.SchemaTypeName = New XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema")

        ' </xs:complexType>
        ct1.Attributes.Add(itemID)

        ' </xs:element>
        item.SchemaType = ct1

        ' </xs:sequence>
        sequence1.Items.Add(item)
        customerOrderType.Particle = sequence1

        ' <xs:attribute name="CustomerID" type="xs:string"/>
        Dim CustomerID As New XmlSchemaAttribute()
        CustomerID.Name = "CustomerID"
        CustomerID.SchemaTypeName = New XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema")

        customerOrderType.Attributes.Add(CustomerID)

        ' </xs:complexType>
        schema.Items.Add(customerOrderType)

        ' <xs:element name="ordersByCustomer">
        Dim ordersByCustomer As New XmlSchemaElement()
        ordersByCustomer.Name = "ordersByCustomer"

        ' <xs:complexType>
        Dim ct2 As New XmlSchemaComplexType()

        ' <xs:sequence>
        Dim sequence2 As New XmlSchemaSequence()

        ' <xs:element name="customerOrders" type="customerOrderType" minOccurs="0" maxOccurs="unbounded" />
        Dim customerOrders As New XmlSchemaElement()
        customerOrders.MinOccurs = 0
        customerOrders.MaxOccursString = "unbounded"
        customerOrders.Name = "customerOrders"
        customerOrders.SchemaTypeName = New XmlQualifiedName("customerOrderType", "")

        ' </xs:sequence>
        sequence2.Items.Add(customerOrders)

        ' </xs:complexType>
        ct2.Particle = sequence2
        ordersByCustomer.SchemaType = ct2

        ' <xs:unique name="oneCustomerOrdersforEachCustomerID">
        Dim element_unique As New XmlSchemaUnique()
        element_unique.Name = "oneCustomerOrdersforEachCustomerID"

        ' <xs:selector xpath="customerOrders"/>
        element_unique.Selector = New XmlSchemaXPath()
        element_unique.Selector.XPath = "customerOrders"

        ' <xs:field xpath="@customerID"/>
        Dim field As New XmlSchemaXPath()
        field.XPath = "@customerID"

        ' </xs:unique>
        element_unique.Fields.Add(field)
        ordersByCustomer.Constraints.Add(element_unique)

        ' </xs:element>
        schema.Items.Add(ordersByCustomer)

        Dim schemaSet As New XmlSchemaSet()
        AddHandler schemaSet.ValidationEventHandler, AddressOf ValidationCallbackOne

        schemaSet.Add(schema)
        schemaSet.Compile()

        Dim compiledSchema As XmlSchema = Nothing

        For Each schema1 As XmlSchema In schemaSet.Schemas()
            compiledSchema = schema1
        Next

        Dim nsmgr As New XmlNamespaceManager(New NameTable())
        nsmgr.AddNamespace("xs", "http://www.w3.org/2001/XMLSchema")
        compiledSchema.Write(Console.Out, nsmgr)

    End Sub

    Public Shared Sub ValidationCallbackOne(ByVal sender As Object, ByVal args As ValidationEventArgs)
        Console.WriteLine(args.Message)
    End Sub
End Class

为此代码示例生成以下 XML 文件。

<?xml version="1.0" encoding="IBM437"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:complexType name="customerOrderType">
        <xs:sequence>
            <xs:element name="item" minOccurs="0" maxOccurs="unbounded">
                <xs:complexType>
                    <xs:attribute name="itemID" type="xs:string"/>
                </xs:complexType>
            </xs:element>
        </xs:sequence>
        <xs:attribute name="CustomerID" type="xs:string"/>
    </xs:complexType>

    <xs:element name="ordersByCustomer">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="customerOrders" type="customerOrderType" minOccurs="0" maxOccurs="unbounded" />
            </xs:sequence>
        </xs:complexType>
        <xs:unique name="oneCustomerOrdersforEachCustomerID">
            <xs:selector xpath="customerOrders"/>
            <xs:field xpath="@customerID"/>
        </xs:unique>
    </xs:element>
</xs:schema>

注解

指定属性或元素值(或者属性或元素值的组合)在指定范围内必须是唯一的。 约束名称在架构中必须唯一。

构造函数

XmlSchemaUnique()

初始化 XmlSchemaUnique 类的新实例。

属性

Annotation

获取或设置 annotation 属性。

(继承自 XmlSchemaAnnotated)
Fields

获取应用为“XML 路径语言”(XPath) 表达式选择器的子级的域集合。

(继承自 XmlSchemaIdentityConstraint)
Id

获取或设置字符串 ID。

(继承自 XmlSchemaAnnotated)
LineNumber

获取或设置 schema 元素引用的文件中的行号。

(继承自 XmlSchemaObject)
LinePosition

获取或设置 schema 元素引用的文件中的行位置。

(继承自 XmlSchemaObject)
Name

获取或设置标识约束的名称。

(继承自 XmlSchemaIdentityConstraint)
Namespaces

获取或设置用于此架构对象的 XmlSerializerNamespaces

(继承自 XmlSchemaObject)
Parent

获取或设置此 XmlSchemaObject 的父级。

(继承自 XmlSchemaObject)
QualifiedName

获取标识约束的限定名,此标识约束保留 QualifiedName 属性的编译后值。

(继承自 XmlSchemaIdentityConstraint)
Selector

获取或设置 XPath 表达式 selector 元素。

(继承自 XmlSchemaIdentityConstraint)
SourceUri

获取或设置加载了架构的文件的源位置。

(继承自 XmlSchemaObject)
UnhandledAttributes

获取或设置不属于当前架构目标命名空间的限定特性。

(继承自 XmlSchemaAnnotated)

方法

Equals(Object)

确定指定对象是否等于当前对象。

(继承自 Object)
GetHashCode()

作为默认哈希函数。

(继承自 Object)
GetType()

获取当前实例的 Type

(继承自 Object)
MemberwiseClone()

创建当前 Object 的浅表副本。

(继承自 Object)
ToString()

返回表示当前对象的字符串。

(继承自 Object)

适用于